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Home›Consumption›Porsche Boxster vs BMW Z4

Consumption comparison

Porsche Boxster Spyder 987 vs BMW Z4 sDrive30i G29: how much do I save per year?

Same car, two powertrains. The simulator below calculates the gap based on your mileage and charging type.

PorschePetrol

Boxster Spyder 987

54.131363 L · 2011

10,9 L/100km

VS
BMWPetrolMost economical

Z4 sDrive30i G29

52 L · 2018

6,1 L/100km

MotorwayRange & chargingPerformance0-100, top speedConsumptionAnnual TCO

Annual mileage

15 000 km/an

5 000 km50 000 km

Simulated driving mix

Drag anywhere on the bar to adjust

Fuel price

Petrol 95 : 1,99 €/L·Diesel : 1,75 €/L

Annual energy cost · 15 000 km

Typical annual usage : Mix 30% city / 50% road / 20% motorway

PorschePetrol

Boxster Spyder 987

Annual energy cost · 15 000 km

3 877€

25,85 € / 100 km

Equivalent to 1 948 L of petrol 95 per year

Weighted consumption
13,0 L/100km
Fuel price
1,99 €/L
Fuel used
1948,4 L per year
BMWPetrolMost economical

Z4 sDrive30i G29

Annual energy cost · 15 000 km

1 890€

12,60 € / 100 km

Equivalent to 949 L of petrol 95 per year

Weighted consumption
6,3 L/100km
Fuel price
1,99 €/L
Fuel used
949,5 L per year
Annual gap Z4 sDrive30i vs Boxster Spyder+1 988 €/an≈ 999 L petrol 95

BMW Z4 sDrive30i G29 costs 1 988 €/an less in energy than Porsche Boxster Spyder 987, over 15 000 km for this driving mix.

≈ 999 L of petrol 95 saved per year

Your savings over the ownership period

Cumulative projection by annual mileage. The cheaper-to-run vehicle widens the gap year after year.

Annual mileage

15 000 km/an

1 year

1 988 €

≈ 999 L petrol 95

3 years

5 964 €

≈ 2997 L petrol 95

5 years

9 939 €

≈ 4995 L petrol 95

10 years

19 879 €

≈ 9989 L petrol 95

Cumulative savings for BMW Z4 sDrive30i G29 versus Porsche Boxster Spyder 987. Excluding purchase, insurance, maintenance and depreciation.

Annual fuel cost breakdown

Projection over 15 000 km/year.

Porsche

Boxster Spyder 987

Fuelkm/year€/kmAnnual cost
Annual fuel1,99 €/L15 000 km0,258 €/km3 877 €
BMW

Z4 sDrive30i G29

Fuelkm/year€/kmAnnual cost
Annual fuel1,99 €/L15 000 km0,126 €/km1 890 €

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Frequently asked questions

On a 100 km mixed trip, the BMW Z4 sDrive30i is about 50% cheaper than the Porsche Boxster Spyder with default parameters. This ratio shifts with your actual energy prices — simulate for your profile.

The BMW Z4 sDrive30i is cheaper across all distances with default rates. If your energy prices differ significantly, simulate to see the real impact on your budget.